1. Field of the Invention
The present invention is directed to a liquid crystal cell having a pair of carrier plates spaced apart to form a chamber for receiving a liquid crystal layer with each of the carrier plates supporting electrical conductive coating forming the electrodes for the cell.
2. The Prior Art
Various structures of liquid crystal cells are known. An example is disclosed in German Offenlegungsschrift No. 2,354,736, which is based on a United States patent application, which matured into U.S. Pat. No. 3,932,026.
Praxis has shown that many liquid crystal displays especially at the edge of their electrode segments have a relatively weak optical contrast, which also increasingly degenerates during the course of operation of the device. When the liquid crystal molecules of the layer are oriented by means of a layer obliquely sputtered on or by means of mechanical processing of the contact surface, these optical disorders are particularly noticeable. It is believed that the responsibility for these optical defects is the fact that there is a surface variation or jump at the boundary between the electrode and the surface of the substrate on the order of 10.sup.-1 .mu.m. During an oblique vapor depositing, this step or variation in the surface level will cast a shadow and also leads to localized irregularities in a microstructure which was physically formed on the surface.
One has attempted to remove their discontinuity at the transitions with one or more coatings, an example is shown in German Offenlegungsschrift No. 2,533,705, which is based on a United States patent application, which matured into U.S. Pat. No. 3,966,305. However, a truly immaculate contrast can be achieved in this way only when one works with particular care and can accept relatively thick coatings.